The invention relates to a medical device for aerosol containers, in which the release of the aerosol and inhalation take place simultaneously or by switching to an intermediate chamber, into which the medicament is first sprayed and then inhaled from that chamber. Conventional aerosol containers frequently have a nozzle needle which can be pushed into the aerosol container in order to spray out the medicament atomized to the fullest possible extent for inhalation.
An inhalation device in accordance with EP 00 08 667 A1 has a housing with a receiving chamber to hold the aerosol container, to which chamber are coaxially connected a vortexing chamber and a mouthpiece. A support, which has a central stepped bore, projects relatively deeply into the vortexing chamber. Into the section of the stepped bore having the larger bore diameter the nozzle needle of the aerosol container introduced into the receiving chamber can be inserted.
Air inlets, through which the air breathed during inhaling is sucked into the vortexing chamber in order to convey the medicament in the vortexing chamber through the mouthpiece into the lungs, open into the vortexing chamber at a relatively large distance from the stepped bore. Located in the mouthpiece area are separate inlet and outlet valves which make it possible, on the one hand, to inhale through the vortexing chamber, and, on the other hand, to exhale independently of the vortexing chamber. The air inlets opening into the vortexing chamber are of relatively small dimensions, and unsuitable, due to their spatial position, to exert a significant effect on the atomization and vortexing of the medicament. The device is relatively long, corresponding to roughly three times the height of a conventional aerosol container, so that it is impossible in general to carry the device around all the time as a hand or pocket device.
With an inhaler in accordance with U.S. Pat. No. 4,852,561, the mouthpiece and the housing forming the aerosol container receiving chamber are located coaxially one behind the other, whereby the opening mechanism for the aerosol container metering valve is fitted to the end of the inhaler opposite the mouthpiece. The receiving chamber for the aerosol container forms a medicament vortexing chamber, into which the relatively small sized air inlets open. When opening the aerosol container metering valve, the medicament released with the propellant agent is deflected about an angle of approximately 90.degree., so that the metering valve can become clogged early.
In using conventional inhalers, there is a danger, due to the relatively small air inlets opening into the vortexing chamber, of so-called "anxiety over breathing", which is additionally reinforced if valve components are located upstream of the inhalation mouthpiece that impair free respiration and form an additional obstruction on which the medicament can collect.
The object of the invention is to create a medical appliance for inhaling metered aerosols in such a way that with the device the atomization and vortexing of the medicament leaving the aerosol container by way of the air inhaled through the device is improved in comparison with conventional devices in order to achieve that the highest possible quantity of medicament is introduced into the bronchial area, and the frequently occurring anxiety over breathing is largely eliminated.